It's not a palm but is a sedge, more closely related to grasses and bromeliads. I've found that when they dry out the foliage dies off and the tubers go dormant until the rains come again. Have never deliberately dried them off but I'd expect it could be done. You need to keep in mind though that dormant tubers are not completely inactive. Drying them out too much could completely desiccate and kill them. Dry soil that they go dormant in isn't absolutely dry but still has some degree of moisture in it. So it's probably better to store them in relatively dry soil.

Thanks!